Ferrous sulfate is a type of iron. You normally get iron from the foods you eat. In your body, iron becomes a part of your hemoglobin and myoglobin. Hemoglobin carries oxygen through your blood to tissues and organs. Myoglobin helps your muscle cells store oxygen.Ferrous Sulfate is an essential body mineral. Ferrous sulfate is used to treat iron deficiency anemia (a lack of red blood cells caused by having too little iron in the body).